JHeatChart is a one class Java API for generating heat map charts that was created because very few charting APIs seem to contain the facility to create heat maps. It is not a full featured charting API and cannot be used to other charts. The generated charts are created as Java Image objects, which can be incorporated into a GUI or saved to a file.
Easy Chart is an object to display several types of charts in Canvas elements. It takes the values, labels, and colors of each point and renders the chart in canvas elements of a given size. Currently, it supports rendering charts of types: line, scatter, column, bar, and pie. The chart background color, grid color and spacing, error, and mouse event handlers are configurable parameters.